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Data Post-Lab Summary Note : some questions will display a variable like "nCount" or "SyInput" instead of an actual number in the data summary. Q# Question Text 5) Scoring Scheme: 3-2-1-1 Part I. In step 8 of Part I, why do you not want any of the water on the outside of the test tube to drip off into the calorimeter? Your View Full Document

Both a and b. You Scored 2 points out of 3 Possible 6) Data Entry - No Scoring Part I. For each trial, enter the precise mass in GRAMS of the "hot" water in the test tube. Your mass precision should be reported to a thousandth of a gram, i.e. 30.034 g. (Use 5 significant figures.) Your Answer: 26.36 No Points Possible Your Answer: 30 No Points Possible Your Answer: 30 No Points Possible 7) Data Entry - No Scoring Part I. For each trial, enter the initial temperature of the "hot" water in the test tube, Tihot water. Your temperature precision should be reported to two-tenths of a degree Celsius, i.e. 99.6oC. Your Answer: 100.3 No Points Possible Your Answer: 100.2 No Points Possible Your Answer: 97 No Points Possible 8) Data Entry - No Scoring Part I. For each trial, enter the final temperature of the mixture in the calorimeter, Tf. This should be the highest temperature reached after mixing. Your temperature precision should be reported to two-tenths of a degree Celsius, i.e. 34.0oC. Your Answer: 40.1 No Points Possible Your Answer: 43 No Points Possible Your Answer: 42 No Points Possible 9) Scoring Scheme: 3-3-2-1 Part I. For each trial, enter the amount of heat lost by the hot water, qhot water. Hints: The specific heat of water is 4.184 J/goC. Be careful with your algebraic sign and remember that the change in temperature is equal to the final temperature minus the initial temperature. Report your answer using 4 digits. Your Answer: -6640 You Scored 3 points out of 3 Possible Your Answer: -7180 No Points Possible Your Answer: -6904 No Points Possible 10) Data Entry - No Scoring Part I. For each trial, enter the precise mass in GRAMS of the "cool" water in the calorimeter. Your mass precision should be reported to a thousandth of a gram, i.e. 70.546 g. (Use 5 significant figures.) Your Answer: 70.1 No Points Possible Your Answer: 70.1 No Points Possible Your Answer: 70.05 No Points Possible 11) Data Entry - No Scoring Part I. For each trial, enter the initial temperature of the "cool" water in the calorimeter, Ticalorimeter. Your temperature precision should be reported to two-tenths of a degree Celsius, i.e. 17.2oC. Your Answer: 23 No Points Possible Your Answer: 23 No Points Possible Your Answer: 23 No Points Possible 12) Scoring Scheme: 3-3-2-1 Part I. For each trial, enter the amount of heat gained by the cool water, qcool water. The specific heat of water is 4.184 J/goC. Report your answer to 4 digits. Note: You should always carry 1 or 2 extra digits beyond the number of significant figures until your final calculation. Your Answer: 5015 You Scored 3 points out of 3 Possible Your Answer: 5866 No Points Possible Your Answer: 5569 No Points Possible 13) Scoring Scheme: 3-3-2-1 Part I. For each trial, calculate the heat gained by the calorimeter, qcalorimeter. This can be done by using the equation: qhotwater = -(qcoolwater + qcalorimeter). Hint: Think about whether qcalorimeter is a positive or negative quantity. Be careful with your negative values here. Remember that (- qhot water) has the opposite algebraic sign value of (qhot water). Report your answer using 4 digits. Note: You should always carry 1 or 2 extra digits beyond the number of significant figures until your final calculation. Your Answer: 1625 You Scored 3 points out of 3 Possible Your Answer: 1314 No Points Possible Your Answer: 1335 No Points Possible 14) Scoring Scheme: 3-3-2-1 Part I. For each trial, calculate the heat capacity of your calorimeter. Report your answer in the correct number of significant figures. This may only be 2 or 3 significant figures. Your Answer: 95 You Scored 3 points out of 3 Possible Your Answer: 65.7 No Points Possible Your Answer: 70.3 No Points Possible 15) Scoring Scheme: 3-3-2-1 Part I. Calculate the average heat capacity for the calorimeter. Report your answer to the correct number of significant figures. Average = Your Answer: 77 You Scored 3 points out of 3 Possible 16) Scoring Scheme: 3-3-2-1 Part I. Calculate a standard deviation for your data of the heat capacity. Standard deviation = Your Answer: 16 You Scored 3 points out of 3 Possible 17) Scoring Scheme: 3-3-2-1 Part I. Calculate a 90% confidence limit for this data. 90% confidence limit = Your Answer: 26.97 You Scored 3 points out of 3 Possible 19) Scoring Scheme: 3-2-1-1 Part II. Why do you want the water to drip off the metal before it is placed in the calorimeter? Your The mass and the initial temperature of the calorimeter water will be incorrect and affect the calculation of the specific heat capacity of the metal. You Scored 2 points out of 3 Possible 20) Data Entry - No Scoring Part II. For each trial, enter the precise mass in GRAMS of the metal. Your mass precision should be reported to a thousandth of a gram, i.e. 122.956 g. (Use 5-6 significant figures.) Your Answer: 183.597 No Points Possible Your Answer: 183.597 No Points Possible Your Answer: 183.597 No Points Possible 21) Data Entry - No Scoring Part II. For each trial, enter the temperature of the boiling water. This will be the initial temperature of the metal, Timetal. Your temperature precision should be reported to two-tenths of a degree Celsius, i.e. 99.8oC. Your Answer: 101.2 No Points Possible Your Answer: 99.8 No Points Possible Your Answer: 100 No Points Possible 22) Data Entry - No Scoring Part II. For each trial, enter the precise mass in GRAMS of the "cool" water in the calorimeter. Your mass precision should be reported to a thousandth of a gram, i.e. 70.546 g. (Use 5 significant figures.) Your Answer: 70.1 No Points Possible Your Answer: 70.1 No Points Possible Your Answer: 70.1 No Points Possible 23) Data Entry - No Scoring Part II. For each trial, enter the initial temperature of the "cool" water in the calorimeter. Your temperature precision should be reported to two-tenths of a degree Celsius, i.e. 17.6oC. Your Answer: 23 No Points Possible Your Answer: 23 No Points Possible Your Answer: 23 No Points Possible 24) Data Entry - No Scoring Part II. For each trial, enter the final temperature of the calorimeter water after placing the metal in the calorimeter, Tf. This should be the highest temperature reached after adding the metal to the calorimeter. Your temperature precision should be reported to two-tenths of a degree Celsius, i.e. 34.0oC. Your Answer: 37 No Points Possible Your Answer: 37 No Points Possible Your Answer: 37 No Points Possible 25) Scoring Scheme: 3-3-2-1 Part II. For each trial, enter the amount of heat lost by the metal, qmetal. Hint: The specific heat of water is 4.184 J/goC. Be careful of your algebraic sign here and remember that the change in temperature is equal to the final temperature minus the initial temperature. Your answer should be reported to 4 digits. Note: You should always carry 1 or 2 extra digits beyond the number of significant figures until your final calculation. Your Answer: -5184 You Scored 3 points out of 3 Possible Your Answer: -5184 No Points Possible Your Answer: -5184 No Points Possible 26) Scoring Scheme: 3-3-2-1 Part II. For each trial, calculate the specific heat of your metal, Csp. Report your answer to 3 digits. Your Answer: 0.44 You Scored 3 points out of 3 Possible Your Answer: 0.45 No Points Possible Your Answer: 0.448 No Points Possible 27) Scoring Scheme: 3-3-2-1 Part II. Calculate the average specific heat for your metal. You should report your average to the correct number of significant figures. This may be only 2 or 3 significant figures. Average = Your Answer: 0.446 You Scored 3 points out of 3 Possible 28) Scoring Scheme: 3-3-2-1 Part II. Calculate a standard deviation for your data of the specific heat of your metal. Standard deviation = Your Answer: 0.0053 You Scored 3 points out of 3 Possible 29) Data Entry - No Scoring Part II. Using the physical properties of your metal, i.e. density & color, identify your metal. Indicate which metal you have by choosing one of the following metals. Your Cu You Scored 0 points out of 0 Possible 30) Scoring Scheme: 3-3-2-1 Part II. Calculate the percent error of your average specific heat as compared to the accepted values listed. Report your answer to the correct number of significant figures. This may be 2 or 3 significant figures. Csp(Pb) = 0.128 J/goC; Csp(Al) = 0.900 J/goC; Csp(Cu) = 0.387 J/goC % Error = Your Answer: 15.3 You Scored 3 points out of 3 Possible 32) Scoring Scheme: 3-2-1-1 Which of the following chemical equations best describes the dissolution of ammonium nitrate in water? Your NH4NO3(s) ==> NH4+(aq) + NO3-(aq); You Scored 2 points out of 3 Possible 33) Data Entry - No Scoring Part III. For each trial, enter the number of GRAMS of ammonium nitrate dissolved in the calorimeter. Your mass precision should be reported to a thousandth of a gram, i.e. 5.546 g. (Use 4 significant figures.) Your Answer: 5 No Points Possible Your Answer: 4.972 No Points Possible Your Answer: 4.968 No Points Possible 34) Scoring Scheme: 3-3-2-1 Part III. For each trial, calculate the number moles of ammonium nitrate used in the reaction. Report your answer to 4 signficant figures, i.e. 0.08765 moles. Your Answer: 0.0625 You Scored 3 points out of 3 Possible Your Answer: 0.06215 No Points Possible Your Answer: 0.0621 No Points Possible 35) Data Entry - No Scoring Part III. For each trial, enter the initial temperature of the water in the calorimeter, Tiwater. Your temperature precision should be reported to two-tenths of a degree Celsius, i.e. 17.5oC. Your Answer: 23 No Points Possible Your Answer: 23 No Points Possible Your Answer: 23 No Points Possible 36) Data Entry - No Scoring Part III. For each trial, enter the final temperature of the calorimeter water after placing the ammonium nitrate in the calorimeter, Tf. This should be the lowest temperature reached after adding the ammonium nitrate to the calorimeter. Your temperature precision should be reported to two-tenths of a degree Celsius, i.e. 9.6oC. Your Answer: 10.2 No Points Possible Your Answer: 12.5 No Points Possible Your Answer: 13.1 No Points Possible 37) Data Entry - No Scoring Part III. For each trial, enter the precise mass in GRAMS of the water in the calorimeter. Your mass precision should be reported to a thousandth of a gram, i.e. 25.546 g. (Use 5 significant figures.) Your 24.83 Answer: No Points Possible Your Answer: 25.15 No Points Possible Your Answer: 26.11 No Points Possible 38) Scoring Scheme: 3-3-2-1 Part III. For each trial, enter the amount of heat gained by the chemical system of ammonium nitrate, qrxn. The specific heat of water is 4.184 J/goC. Report your answer using 4 digits. Your Answer: 2315 You Scored 3 points out of 3 Possible Your Answer: 1913 No Points Possible Your Answer: 1844 No Points Possible 39) Scoring Scheme: 3-3-2-1 Part III. The heat transfer in the calorimeter is taking place at constant pressure. Therefore, we can equate the heat gained by the chemical system of ammonium nitrate, qrxn, to its enthalpy of the dissolution reaction, ?Hrxn. For each trial, calculate the enthalpy of the reaction per mole of ammonium nitrate in units of Joules per mole. Your answer should be reported in the correct number of significant figures. This may be only 2 or 3 significant figures. Your Answer: 37040 You Scored 3 points out of 3 Possible Your Answer: 30780 No Points Possible Your Answer: 29694 No Points Possible 40) Scoring Scheme: 3-3-2-1 Part III. Calculate the average enthalpy of reaction for the dissolution of ammonium nitrate in J/mol. Your answer should be reported to the correct number of significant figures. Average = Your Answer: 32505 You Scored 3 points out of 3 Possible 41) Scoring Scheme: 3-3-2-1 Part III. Calculate the standard deviation of your measured values of the enthalpy of reaction for the dissolution of ammonium nitrate. Std dev = Your Answer: 3965 You Scored 3 points out of 3 Possible 42) Scoring Scheme: 3-3-2-1 Part III. Is the dissolution reaction of ammonium nitrate enthalpy favored? Your No, it is not enthalpy favored since the chemical system gains energy. You Scored 3 points out of 3 Possible 44) Scoring Scheme: 3-2-1-1 Which of the following chemical equations best describes the neutralization reaction of hydrochloric acid and sodium hydroxide? Your HCl(aq) + NaOH(aq) ==> H2O(l) + NaCl(aq); You Scored 3 points out of 3 Possible 45) Data Entry - No Scoring Part IV. For each trial, enter the precise volume in mL of 6.0 M HCl used to measure the enthalpy change in the neutralization reaction. Your Answer: 15 No Points Possible Your Answer: 15 No Points Possible Your Answer: 15 No Points Possible 46) Scoring Scheme: 3-3-2-1 Part IV. For each trial, calculate the number moles of 6.0 M HCl used in the reaction. Report your answer using 4 digits. Note that it is 1 or 2 digits beyond the number of significant figures, i.e. 0.2345 moles. Your Answer: 0.09 You Scored 3 points out of 3 Possible Your Answer: 0.09 No Points Possible Your Answer: 0.09 No Points Possible 47) Data Entry - No Scoring Part IV. For each trial, enter the initial temperature of the HCl solution. Your temperature precision should be reported to two-tenths of a degree Celsius, i.e. 17.4oC. Your Answer: 22 No Points Possible Your Answer: 22 Your Answer: 22 No Points Possible No Points Possible 48) Data Entry - No Scoring Part IV. For each trial, enter the final temperature of the calorimeter water, Tf. This should be the highest temperature reached after mixing the HCl and NaOH in the calorimeter. Your temperature precision should be reported to two-tenths of a degree Celsius, i.e. 30.0oC. Your Answer: 65.5 No Points Possible Your Answer: 65.5 No Points Possible Your Answer: 65.5 No Points Possible 49) Data Entry - No Scoring Part IV. For each trial, enter the precise volume in mL of 6.0 M NaOH used to measure the enthalpy change in the neutralization reaction. Your measurement should be reported to the closest five-tenths of a mL. (e.g. 15.5 mL). Your Answer: 15 No Points Possible Your Answer: 15 No Points Possible Your Answer: 15 No Points Possible 50) Scoring Scheme: 3-3-2-1 Part IV. In order to calculate the heat gained by the water in the calorimeter, the mass of the water must be determined. It will be calculated from the volumes of HCl and NaOH and the density of water, 1.00 g/mL. You should approximate that the density of the NaOH and HCl mixture is equal to the density of water. For each trial, calculate the mass of water in the calorimeter. Report your values to 3 significant figures. Your Answer: 30 You Scored 3 points out of 3 Possible Your Answer: 30 No Points Possible Your Answer: 30 No Points Possible 51) Scoring Scheme: 3-3-2-1 Part IV. For each trial, enter the amount of heat lost by the chemical system, qrxn. Hints: The specific heat of water is 4.184 J/goC. Be careful of your algebraic sign here and remember that the change in temperature is equal to the final temperature minus the initial temperature. Report your answer using 4 digits. Note, this is 1 or 2 digits beyond the correct number of significant figures. Your Answer: -8810 You Scored 3 points out of 3 Possible Your Answer: -8810 No Points Possible Your Answer: -8810 No Points Possible 52) Scoring Scheme: 3-3-2-1 Part IV. The heat transfer in the calorimeter is taking place at constant pressure. Therefore, we can equate the heat lost by the chemical system, qrxn, to its enthalpy of reaction, ?Hrxn. For each trial, calculate the enthalpy of the neutralization reaction per mole of hydrochloric acid in units of Joules per mole. Do not forget about your algebraic sign here. Your answer should be reported in the correct number of significant figures. This should be 3 digits. Your Answer: -97889 You Scored 3 points out of 3 Possible Your Answer: -97889 No Points Possible Your Answer: -97889 No Points Possible 53) Scoring Scheme: 3-3-2-1 Part IV. Calculate the average enthalpy of reaction for the neutralization reaction in J/mol. Your answer should be reported in the correct number of significant figures. This may be 2 or 3 significant figures. Average = Your Answer: -97889 You Scored 3 points out of 3 Possible 54) Scoring Scheme: 3-3-2-1 Part IV. Calculate the standard deviation of your measured values of the enthalpy for the neutralization reaction. Std dev = Your Answer: 0 You Scored 3 points out of 3 Possible 55) Scoring Scheme: 3-3-2-1 Part IV. Is the neutralization reaction enthalpy favored? Your Yes, it is enthalpy favored since the chemical system loses energy. You Scored 3 points out of 3 Possible 57) Data Entry - No Scoring Part V. For each trial, enter the precise mass in GRAMS of the water in the calorimeter before adding the ice. Your mass precision should be reported to a thousandth of a gram, i.e. 70.546 g. (Use 5 significant figures.) Your Answer: 25 No Points Possible Your Answer: 25 No Points Possible Your Answer: 25 No Points Possible 58) Data Entry - No Scoring Part V. For each trial, enter the initial temperature of the water in the calorimeter before adding the ice. Your temperature precision should be reported to two-tenths of a degree Celsius, i.e. 17.6oC. Your Answer: 23 No Points Possible Your Answer: 23 No Points Possible Your Answer: 23 No Points Possible 59) Data Entry - No Scoring Part V. For each trial, enter the final temperature of the calorimeter water after placing the ice in the calorimeter, Tf. This should be the lowest temperature reached after adding the ice to the calorimeter. Your temperature precision should be reported to two-tenths of a degree Celsius, i.e. 1.0oC. Your Answer: 2.8 No Points Possible Your Answer: 5 No Points Possible Your Answer: 4 No Points Possible 60) Scoring Scheme: 3-3-2-1 Part V. For each trial, enter the amount of heat lost by the calorimeter water, qwater. Hint: The specific heat of water is 4.184 J/goC. Be careful of the algebraic sign here and remember that the change in temperature is equal to the final temperature minus the initial temperature. Report your answer using 4 digits. Note, this is 1 or 2 digits beyond the correct number of significant figures. Your Answer: -2113 You Scored 3 points out of 3 Possible Your Answer: -1883 No Points Possible Your Answer: -1987 No Points Possible 61) Scoring Scheme: 3-3-2-1 Part V. For each trial, enter the amount of heat lost by the calorimeter, qcalorimeter. Be careful of the algebraic sign here and remember that the change in temperature is equal to the final temperature minus the initial temperature. Report your answer using 4 digits. Note, this is 1 or 2 digits beyond the correct number of significant figures. Your Answer: -1555 You Scored 3 points out of 3 Possible Your Answer: -1386 No Points Possible Your Answer: -1463 No Points Possible 62) Data Entry - No Scoring Part V. For each trial, enter the precise final mass in GRAMS of the water in the calorimeter AFTER the ice has melted. Your mass precision should be reported to a thousandth of a gram, i.e. 75.546 g. (Use 5 significant figures.) Your Answer: 35 No Points Possible Your Answer: 35 No Points Possible Your Answer: 35 No Points Possible 63) Data Entry - No Scoring Part V. Enter your measured temperature of an ice-water bath. This is the initial temperature of the melted ice and is needed to calculate the temperature change of the melted ice. If you did not measure the temperature of an ice-water bath with your thermometer simply assume that it is 0.0oC. Measuring this temperature with your thermometer would eliminate any systematic errors introduced by your thermometer since the temperature change is measured by difference. Your temperature values should be reported to two-tenths of a degree, i.e. 0.2oC. Tiice-water = Your Answer: 0 No Points Possible 64) Scoring Scheme: 3-3-2-1 Part V. The heat gained by the ice melted the ice and raised the temperature of the melted ice from its initial temperature to the final temperature of the water in the calorimeter. Use this information to calculate the heat of fusion per gram of ice for each trial. Enter your values using the correct number of significant figures. This may be 2 or 3 digits. Your Answer: 355 You Scored 2 points out of 3 Possible Your Answer: 306 No Points Possible Your Answer: 328 No Points Possible 65) Scoring Scheme: 3-3-2-1 Part V. Calculate the average Heat of Fusion of ice in J/g. Your answer should be reported in the correct number of significant figures. This should be 3 digits. Average = Your Answer: 330 You Scored 3 points out of 3 Possible 66) Scoring Scheme: 3-3-2-1 Part V. Calculate the standard deviation of your measured values of the Heat of Fusion of ice. Std dev = Your Answer: 25 You Scored 3 points out of 3 Possible 67) Scoring Scheme: Analysis Part V. Calculate your percent error. The accepted value for the Heat of Fusion of ice, according to the textbook, Petrucci et. al., 8th edition, is 330 J/g. Note that this value is reported here only to 2 significant figures. % error = Your Answer: 0 You Scored 5 points out of 5 Possible ...